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By what factor should the length of a simple pendulum be changed in order to triple the period of vibration?

1 Answer
Jan 13, 2018


9 times of the previous length


Relation between time period T and length l of pendulum is given as T #prop# √l
So, we can write,
#(T2)/(T1)# = #√(l2)/(l1) # (where T1 and T2 are initial and final time period and L1 and L2 are initial and final length of the pendulum respectively as required)
Given, T2 = 3 T1
So, #(l2)/(l1)# will be 9
Hence length should be made 9 times than that of the previous value.